Citrus juice extraction on a commercial scale can be advantageously performed with a juice extractor. For example, the FMC Inline Juice Extractor manufactured by the assignee of the present invention, includes upper and lower cups that move relative to one another along a reciprocal path of travel. The sides of both the upper and lower cups typically comprise fingers that support a fruit so that it can be squeezed without bursting. The fingers of the upper cup interdigitate or intermesh with those of the lower cup.
An orange or other citrus fruit can be fed, for example, to the bottom cup by a cam-operated feeding device. The upper and lower cups are then brought together so that the respective fingers of the cup intermesh and the fruit therebetween is accordingly squeezed.
Sharp, typically circular, cutters are positioned in the top and bottom cups. As the cups move relative to one another, the fruit is pressed against the cutters. The cutters cut plugs from both the top and bottom portions of the fruit as the interdigitating fingers of the two cups mesh together.
The cutting of the plug from the top portion of the fruit promotes separation of the peel from the internal portions of the fruit (i.e., juice and pulp). The plug cut from the lower portion of the fruit allows the internal portions of the fruit to be forced down into a strainer tube positioned just below the lower cup cutter. The strainer tube, in turn, is positioned within a manifold.
After the internal portions of the fruit have been squeezed into the strainer tube, an orifice tube moves upward into the strainer tube applying pressure to the internal portion of the fruit therein. This causes the juice and juice sacs, due to their small particle size, to flow through small holes of the strainer tube and into the juice manifold, thus separating out the juice and pulp.
Further details relating to an examplary citrus juice extractor may be found in U.S. Pat. No. 7,156,016 to Schrader et al., assigned to the assignee of the present invention, and the entire contents of which are incorporated herein by reference.
When the strainer tube of the juice extractor fails, it typically will fail by tearing of the material between the holes in the wall of the strainer tube creating an enlarged opening. The unwanted opening then allows an undesired material release to contaminate the downstream processing equipment and the products produced by this equipment. The undesired material release from the extractor will typically include the core material, peel material, and seeds into the pulpy juice stream. Detection of this failure often occurs after an extended period of time causing loss of product as well as extended apparatus downtime.
Because the strainer tube is located inside the juice extractor and is not readily visible to a service person, locating the point of failure may require that each juice extracting machine on the line be partially disassembled and the strainer tubes visually inspected. As a result, the extraction process is halted until all of the extractors have been inspected to determine the failed strainer tube or tubes, and in what extractors they have failed.
A juice finisher is another type of citrus juice processing device that may typically be coupled downstream from the juice extractors. The typical juice finisher may be either a screw type finisher and/or a paddle finisher. Both types rely on the juice to be extruded through a screen material that, in turn, regulates the size of the pulp that is maintained within the juice stream. Any pulp that is too large to be extruded through the screen is compressed by centrifugal and mechanical force that is created by limiting the flow of pulp discharge either by a back pressure regulator, and/or a weighted gate. The feed rate and the pulp-to-juice ratio of the feed material may have an important effect on the level of dryness at given conditions. Feed forward control is often used based on historical data; however, another significant advance in the control of a juice finisher is disclosed in U.S. Pat. No. 6,375,996, assigned to the assignee of the present invention, and the entire contents of which are incorporated herein by reference. The patent discloses measuring pulp dryness using nuclear magnetic resonance (NMR). Based on the results of the NMR measurement, the juice injection into the finisher, the speed of the juice finisher, and/or the discharge pressure from the juice finisher is regulated.
Nevertheless, should the screen material fail or be ruptured in the juice finisher, undesired material will be released with the juice flow. In other words, the juice finisher represents another citrus processing device that when subject to malfunction may experience a release of undesired material into the juice stream. In the case of the juice finisher, the undesired material is additional pulp.